YouTube has pledged to revise its “restricted mode” settings to stop filtering out LGBTQ-related content after Canadian indie pop duo Tegan and Sara pointed out that their music videos were being blocked from view, the Guardian reports.

On Saturday, Pop Crave, which curates pop-culture news across social platforms, tweeted that the filter was indiscriminately weeding out videos with an LGBTQ theme. Prodigious YouTubers began to take note — one LGBTQ YouTube star from England, Calum McSwiggan, posted a video on March 18 called, “This Video is Too Gay for Kids,” explaining that if you turn on the restricted mode setting, all but one of his videos disappear.

The next day, Tegan and Sara posted a message on Twitter noting that if a user has YouTube on restricted mode, “a bunch of our music videos disappear…SAD!”

If you put @YouTube on restricted mode a bunch of our music videos disappear. I checked myself. LGBTQ people shouldn't be restricted. SAD!

Restricted mode is an optional setting used to filter out potentially “mature” content for viewers under 18; you can find it if you scroll down to the bottom of a YouTube page. School or library administrators, not to mention anxious parents, can choose to keep the setting on. A YouTube spokesperson told the Guardian, “Some videos that cover subjects like health, politics and sexuality may not appear for users and institutions that choose to use this feature.”

Over the weekend, Tegan and Sara — sisters who are both openly gay — noticed that some of their videos weren’t showing up when YouTube’s restricted mode was turned on. The music videos for “That Girl” and “U-Turn,” both off their 2016 album Love You to Death, weren’t showing up. Neither video is sexually “explicit” in any way; the former intersperses candid, backstage footage of the pair with scenes of them performing for adoring crowds, while the latter shows the sisters singing over faux-retro animation. It’s hard to picture two more innocuous-looking music videos.

Soon after Tegan and Sara posted their tweet, others joined in, including YouTube personality and LGBTQ activist Tyler Oakley, who pointed out that a video of his titled, “8 Black LGBTQ+ Trailblazers Who Inspire Me” was blocked under the restricted mode filter. Apparently according to YouTube, motivational videos made by and for queer kids may as well have been hardcore pornography.

On Monday, YouTube responded to the growing chorus by tweeting out an apology “for all the confusion with Restricted Mode” and assuring users that they’re working to fix the problem.

Sorry for all the confusion with Restricted Mode. Some videos have been incorrectly labeled and that’s not right. We're on it! More to come.

Later, YouTube told the Guardian, “We recognize that some videos are incorrectly labelled by our automated system and we realize it’s very important to get this right. We’re working hard to make some improvements.”